Double or multiple panes of insulating glass are being used to an ever increasing extent in high-rise construction because of their heat insulating characteristics. For its production, however, hitherto relatively complicated and expensive processes were necessary. The reason for this is that high demands are made of the frame connecting the panes. It must be absolutely tight against moisture and it must not lose this characteristic even after decades of use under the usual weather dependent temperature conditions. In practice only such thermal panes have proven themselves essentially in the case of which the surrounding rim strip consists of lead and is connected with the glass panes by a cementing or sealing mass. Furthermore, insulating double panes have been known in the case of which the edges of the glass panes running in parallel at a distance from one another are directly fused together. Both processes require expensive production arrangements at the place of fabrication which can be equipped only for a limited number of different formats of panes moreover for reasons of rationalization.
So far no one succeeded in creating double pane insulating glass with a frame made of plastic because hiterto it had not been possible to produce a faultless sealing connection between the glass and the plastic by gluing or some other means.